This is one of the primal sauces. Master it and you will be able to cook so many things without having to open cans or packets. Put it in things, on things, next to things. Gussy it up, dress it down, it's one of the most versatile sauces around. Make sure you read the Variations for a few suggestions to get you going.
Learning to cook a few basic sauces is beneficial on many levels - you are in control of the ingredients (this may be very important to you if your are on a fat or sodium restricted diet), it's often cheaper, it tastes a lot better, and the simple act of creating a sauce that has been made by not only You, but nearly every famous chef in existence is incredibly mindful.
The next time you are tempted to buy a packet of white sauce mix and read the ingredients on the package. Bechamel is simply the French name for what many refer to as White Sauce. Then compare that list on the package to the recipe ingredients below and think about what you really want to eat.
If you are interested in nutrition facts, here they are (set for those that use skim milk as I am assuming that if you click the word here, you are a calorie counter and looking for lower calories).
Ingredients that do not include anything with a lengthy chemical name or something to make sure there was no settling or glumping of powder:
2 T unsalted butter is best, but use the kind you prefer
3 T flour
2 C hot milk (use whole, 2% or skim as is your preference. The calories above are run using skim)
Salt to taste
Ground white pepper to taste
A pinch of nutmeg or thyme is very good in this sauce.
Directions that are almost as easy as those on the packet:
Melt the butter in a medium sized sauce pan over medium heat. Stir in the flour until it is thoroughly incorporated into the butter - about two minutes will help remove the "floury" taste and that's where many people mess up when making Bechamel. Remove from heat.
Heat the milk in your preferred way - I've done it in a small pan or in the microwave. Either way is fine but get it hot. It should be heating while you are prepping the butter and flour.
Dump the hot milk into the butter/flour mixture and vigorously stir or whisk to make sure the sauce is not lumpy.
Return it to the medium heat and bring it to a boil - stir or whisk the entire time it is coming to a boil.
Then lower the temp and simmer for another two minutes. Season with the salt, white pepper, and nutmeg to your taste.
Add cheese after the final simmer if you are making something deliciously cheesy.
Or make it even more savory - skip the nutmeg, add some black pepper or browned and drained breakfast sausage, it's great over a biscuit.
Skip the salt and make sure you use skim milk to lower the fat and sodium. You may want to ramp up the pepper and definitely add the bit of thyme.
Need to lower the calories even more or do not use milk? Make Veloute instead!